The present program on post-genome discovery focuses on the elucidation of the stereochemical conformation of an individual biomolecule, and will direct itself on more and more important studies on the interactions with the other biomolecules and the accompanying conformational changes. Those studies require efficient techniques, such as NMR measurement, to develop.
However, it is difficult for conventional NMR measurement technique that a thousand kinds of low molecular compounds for example are screened for substances interacting with a protein in interest. In such case, a procedure is presumed that the protein is mixed with ten kinds of low molecular compounds to prepare a measurement sample solution, which is then subjected to primary screening. However, the procedure needs preparing hundred sample solutions and making hundred turns of NMR measurement/analysis, and hence it takes a lot of time and a large amount of labor consumed to carry out this procedure repeatedly.
An automatic measurement sample changer can be applied to an NMR-measuring apparatus to improve the efficiency of the procedure, but it saves only a manual work for measurement sample exchange, and does not at all contribute to save the amount of the protein to use, the job for measurement sample preparation, and measurement time to consume.
The method for measuring solution NMR includes gel phase NMR analysis and liquid chromatography NMR analysis, but they have insufficient capacity to trace the conformational change of a protein, particularly the midterm process toward the folding of the protein.
The technique for measuring a measurement sample using an NMR method precedent to the present invention includes a technique wherein a filler is provided in the sample pathway inside an NMR probe to absorb the sample and then the absorbed sample is subject to NMR measurement (Patent document 1). However, the filler is provided in the sample pathway to concentrate the sample and prevent diffusion of the sample, and a screening method is not disclosed at all.
The technique for measuring a target polymeric substance using an NMR method precedent to the present invention includes a technique wherein the target polymeric substance is immobilized on a solid phase to make NMR measurement (Patent document 2). According to this technique, the target polymeric substance is immobilized on a solid phase under a liquid environment to make NMR measurement, or the immobilized substance is further supplied with a candidate compound to make NMR measurement about the result of their interaction. However, this system can not determine the process of their interaction by NMR, and can not conduct high throughput screening wherein many candidate compounds are consecutively supplied to measure. It is far from sufficient to effectively measure a sample.
[Patent document 1] Japanese Patent Application Laid-Open No. 2002-139558
[Patent document 2] Japanese Patent Application Laid-Open No. 2004-138545